Researchers
Find Children Exposed to Pyrethroid Insecticides in the Home
(Beyond Pesticides, September 6, 2006) According to
researchers at Emory University and the Centers for Disease Control
and Prevention (CDC), residential pesticide use represents the most
important risk factor for children's exposure to pyrethroid insecticides.
The study, A
Longitudinal Approach to Assessing Urban and Suburban Children's Exposure
to Pyrethroid Pesticides, is published in the September 2006
issue of Environmental Health Perspectives (Vol. 114, No. 9).

The results are
part of a larger study examining the impacts of dietary and residential
exposure of children to organophosphate (OP) and synthetic pyrethroid
pesticides. With the phaseout of most residential uses of the common
OP insecticides, chlorpyrifos and diazinon, home use of pyrethroids
has increased. Pesticide products containing synthetic
pyrethroids are often described by pest control operators and community
mosquito management bureaus as “safe as chrysanthemum flowers.”
While pyrethroids are a synthetic version of an extract from the chyrsanthemum
plant, they were chemically engineered to be more toxic, take longer
to breakdown, and are often formulated with synergists, increasing potency
and compromising the human body’s ability to detoxify the pesticide.
Pyrethroids may affect neurological development, disrupt hormones, induce
cancer, and suppress the immune system.

The authors conducted
a longitudinal study to assess the exposure of 23 elementary school–age
children to pyrethroid pesticides, using urinary pyrethroid metabolites
as exposure biomarkers. The 15-consecutive-day sampling period was divided
into three phases. During phase 1 (days 1–3) and phase 3 (days
9–15), children consumed their normal conventional diets. During
phase 2 (days 4–8), organic food items, including fresh fruits
and vegetables, juices, processed fruit or vegetables (e.g., salsa),
and wheat- or corn-based items (e.g., pasta, cereal, popcorn, or chips),
were substituted for the children's conventional diet. These food items
are routinely reported to contain pesticide residues by the U.S. Department
of Agriculture (USDA). During the 15 days, urine samples were analyzed
for five common pyrethroid metabolites. The researchers also surveyed
the children's parents for residential pesticide use. Comparing metabolites
between dietary phases, the researchers saw no apparent trend. However,
seven children in families that reported using pyrethroid pesticides
had significantly higher metabolite levels than the other children.

Furthermore, children's
ages appear to be significantly associated with pyrethroid exposure,
which is likely attributed to the use of pyrethroids around the premises
or in the facilities where older children engaged in outdoor activities.
The researchers conclude that an organic diet alone is unlikely to dramatically
decrease a child's exposure to pyrethroids the way it does exposure
to OP pesticides. Limiting residential use of pyrethroids and preventing
children's contact with treated areas are essential in reducing children's
exposure to these harmful pesticides.